\documentclass[tikz,border=2mm]{standalone}
\usepackage{array,amsmath,mathptmx,xcolor,pifont,fontspec,xunicode-addon}
\usepackage{bbding}
\usepackage[UTF8]{ctex}
\newcolumntype{C}[1]{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
\usepackage{tikz-cd}
\usepackage{tikz,graphicx,subfig,caption} % Required for drawing custom shapes
\usetikzlibrary{fit,matrix,chains,arrows,shapes,positioning,arrows.meta,chains,shadows,shapes.callouts,decorations.text,shapes.symbols,shapes.misc, positioning,decorations.pathreplacing,calc,backgrounds,}

% 额外添加
\usepackage{indentfirst}
\usepackage{diagbox}
\usepackage{pifont}


\begin{document}
	\begin{tikzpicture}[>=latex, scale=1.5, every node/.style={anchor=south west,inner sep=0,fill=white}]
		
		\node(I0)[align=center,fill=white] at (0,0){\textcircled{\footnotesize{0}}};
		\node(I1)[align=left,fill=white] at ([xshift=3em, yshift=-0.05em]I0.south){\ding{172}\_};
		
		\node(I2)[align=left,fill=white] at ([xshift=3em, yshift=-2em]I0.south){\ding{173}};
		\node(I3)[align=left,fill=white] at ([xshift=3em, yshift=-0.25em]I2.east){\ding{174}};
		\node(I4)[align=left,fill=white] at ([xshift=3em, yshift=-0.3em]I3.east){\ding{175}\_};
		
		\node(I5)[fill=white] at ([xshift=2em, yshift=-2.5em]I2.east){\ding{176}};
		\node(I6)[fill=white] at ([xshift=3em, yshift=-0.3em]I5.east){\ding{177}\_};
		
		
		\node(I7)[fill=white] at ([xshift=3.5em, yshift=-4.5em]I2.east){\ding{178}\_};
		
		% %连接线
		\draw[->] (I0.east) -- node[above]{Z}(I1.west);
		\draw[->] (I0.south) |- (I2.west);
		\draw[->] (I2.east) -- node[above]{A}(I3.west);
		\draw[->] (I3.east) -- node[above]{b}(I4.west);
		\draw[->] (I2.south) |- (I5.west);
		\draw[->] (I5.east) -- node[above]{A}(I6.west);
		\draw[->] (I2.south) |- (I7.west);
		\draw [->] (I5.south) -- ([xshift=-0.5em]I7.north);
		\path
		(I5) [->] edge [loop above] node{c} ();
		
		%       % 额外的数据
		\node(+) at ([xshift=-1em,yshift=-0.5em]I0.south){\small{+}};
		\node(OK) at ([xshift=-0em,yshift=0em]I1.east){\small{OK}};
		\node(a) at ([xshift=-1.5em,yshift=0em]I2.west){\small{a}};
		\node(c) at ([xshift=-1.5em,]I5.west){\small{c}};
		\node(d) at ([xshift=-2.5em,]I7.west){\small{d}};
		\node(r1) at ([xshift=-0.3em,yshift=0em]I4.east){\small{r(1)}};
		\node(r2) at ([xshift=-0.3em,yshift=0em]I6.east){\small{r(2)}};
		\node(r3) at ([xshift=-0.3em,yshift=0em]I7.east){\small{r(3)}};
		\node(d1) at ([xshift=0.4em,yshift=-1em]I5.east){\small{d}};
		
		
		
		\begin{pgfonlayer}{background}
			\node [draw, fill=white,fit=(I0)(I1)(I2)(I3)(I4)(I5)(I6)(I7)(r1)(r2)(r3)(+),inner sep=1.0em] {};
		\end{pgfonlayer}
		
		
		
	\end{tikzpicture}
\end{document}